The 'Rules' for metal detecting in Bermuda are as follows:
1) technically you need to get a liscence from the Agricultural Dept. which states where and when you will be hunting, this costs nothing and most detectorists locally and certainly visiting detectorists don't do this, the fee is $0.00 so go figure
2) the parks dept. and lifeguards will ask you to leave major tourist beaches between the hours of 11 am and 6 pm from April to October, but they will only do this sometimes, be polite and no worries
3) show respect for others by filling your holes, not hunting old historic forts or cemeteries just the same as if you were stateside, it's just common courtesy
4) some beaches are private which means that the access to them is private but anything below the high tide mark is considered Queen's Bottom or public domain, mention that term and most people will leave you alone as it is the law, getting to them without trespassing is of course the problem
5) always be courteous and polite and you will go far in a country that prides itself on it's civility. Good Morning and Good Afternoon are a very good start and will identify you as a civilized person to the local populous
6) you may be asked to pay duty when bringing something like a metal detector into the country (there are no taxes here so the government must generate income somehow), coming by cruiseship it shouldn't be a problem but if the customs officer asks for duty suggest an exemption for the length of your stay and give a highly depreciated value as you may still be asked to pay 33% duty. Remember that one good ring will negate the duty and then some
7) send me a PM and perhaps we can hunt together during your visit
Cheers,
BDA